It seems every time I do design with number of round boxed in a design I end up with too much extra code which I don't really like. Yes I can use a javascript to generate the round corners to cut down the code little bit but it doesn't work correctly in all browsers so have to stick just with pure css. Too bad most current browsers doesn't support CSS3 properties for the round corners I think only latest version of Mazilla has support for it but it's not enough to start using it.
This is the closest I've come to achieving rounded corners with the least markup and no javascript. It's basically a pared down hybrid version of a lot of techniques out there.
I'm probably alone in this, but until CSS3 or better browser support, I'm avoiding the technique altogether unless a client specifically asks for it. It still feels too hacky, kind of like the nested table tricks we used to pull back in 2000 just to achieve certain border effects.